State-of-the-art documents disclose ventilation or air-conditioning installations for vehicles, especially rail vehicles and road vehicles, which installations include shutter devices for shutting off air-conditioning ducts.
Document FR 2 461 606 (1979) to AIR INDUSTRIE and to SOCIETE NATIONALE DES CHEMINS DE FER FRANCAIS describes an air-conditioning installation for a public transport vehicle. That installation includes air-conditioning means for feeding a distribution duct under pressure, first localized distribution devices interconnected with one another permanently via said distribution duct, and second localized distribution devices, each of which is fed intermittently also from said distribution duct.
That document teaches that a shutter member controlled by control means can be used to enable the localized distribution devices to be shut off.
That shutter member is constituted by a valve member formed by a metal disk and by a disk made of a soft material for leak-proofing the valve on closure.
Such an air-conditioning installation suffers from the drawbacks that the flexible means implemented are bulky, noisy, and tend to become worn.
Such shutter members also suffer from the drawbacks of being costly, and fragile, and of preventing the distribution duct in which they are installed from being cleaned easily and quickly.
Another drawback of such prior art shutter members is that they are difficult to replace.
Another drawback of those prior art shutter members is that they distribute the air intermittently, whereas the device of the invention by the Applicant applies to continuous distribution which improves comfort.
Another drawback of those prior art shutter members is that electrical or pneumatic power must be supplied to each shutter member.
Document EP 0 315 108 (1987) to HITACHI describes a ventilation installation for rolling stock. That installation includes air feed means for sucking in air from outside a vehicle and feeding it into said vehicle, and exhaust means for exhausting the air from the inside of the vehicle to the outside thereof.
That document teaches that flexible means in the form of plates can be used for reducing the cross-sectional areas of the respective air-flow passages as a function of changes in the pressure of the outside air.
Such a ventilation installation and such shutter means suffer from the above-mentioned drawbacks.
Document FR 2 693 698 (1992) to the Applicant concerns air-conditioning apparatus enabling sudden changes in the pressure inside the vehicles to be avoided.
That air-conditioning apparatus includes, inter alia, shutter means for shutting off the pipes via which outside air is sucked in, and inside air is rejected.
Those shutter means are constituted by flaps matching the dimensions of the pipes. They are disposed in the vicinity of the inlet and of the outlet of the air-conditioning apparatus. They are mounted to swing about respective arms secured to one of their sides, by means of hinge systems associated with the walls of the pipes. The arms are rotated by respective actuators fixed to the structure of the vehicle.
Unfortunately, such air-conditioning apparatus and such shutter means do not enable the above-mentioned drawbacks to be remedied.
State-of-the-art documents also disclose shutter devices that can be applied to ventilation or air-conditioning installations for vehicles, especially rail vehicles and road vehicles.
Documents EP 0 523 752 (1987) and EP 0 315 108 (1987), both to HITACHI, describe an air-flow regulation device placed in the ventilation circuit of a rail vehicle, for regulating the air-flow when the vehicle is in motion, the vehicle including at least one pipe putting the air contained inside the vehicle into communication with the air outside the vehicle. That device includes means for preventing or limiting air flow through the pipe in the event of a sudden change between the pressure outside the vehicle and the pressure inside said vehicle.
As indicated above, such a ventilation installation and such shutter means suffer from the above-defined drawbacks.
State-of-the-art documents also disclose other shutter devices that might be applied to ventilation or air-conditioning installations for vehicles, especially for rail vehicles or road vehicles.
Document DE 371 783 (1923) to SILLER & BODENKIRCHEN describes shutter means comprising two shutter elements, each of which is formed by a part that fits snugly inside a pipe, and that is provided with a through aperture via which air can flow, the aperture opening out in a partition-receiving face of the part, the partition-receiving faces of the two elements facing each other, the partition being a blade that is fixed via one of its sides, and that, in the event of a sudden change between the pressure inside the vehicle and the pressure outside said vehicle, is capable of being pressed against the partition-receiving face of one of the shutter elements so as to close its aperture entirely in the event of pressure change in a given direction, and of being pressed against the partition-receiving face of the other shutter element so as to close its aperture in the event of pressure change in the other direction.
Document U.S. Pat. No. 3,260,274 (1966) to J. P. MORGAN describes a valve comprising:
at least one shutter element A, B disposed inside a pipe so as to leave a passage through which a flow can pass, the shutter element having a "partition-receiving" face; and PA1 at least one partition disposed transversely relative to the flow, and situated in the vicinity of the partition-receiving face 15, 16 of the shutter element A, B, the partition being deformable under pressure. PA1 each of the longitudinally-extending inflatable means is in the form of a hollow flexible longitudinal strip that is closed at both of its ends so as to constitute a chamber, and that is provided with an air inlet/outlet orifice; PA1 each of the longitudinally-extending inflatable means is in the form of a succession of hollow flexible longitudinal strip segments, each of which is closed at both of its ends so as to constitute a chamber, and is provided with a respective air inlet/outlet orifice; and PA1 each of the longitudinally-extending inflatable means is provided, on its side that is perpendicular to the floorward-facing blow perforations, with an outwardly-extending projection designed to co-operate with the extrusion so as to come into close contact with a facing portion of the extrusion.
In the event that the inside pressure and the outside pressure are equal, the partition leaves an unobstructed flow passage, and in the event of sudden change between the inside pressure and the outside pressure, the partition is pressed against said partition-receiving face so as to shut off the flow passage.
Document U.S. Pat. No. 3,260,274 to J. P. MORGAN also discloses that the valve comprises two shutter elements A & B, each of which is formed by a part that fits snugly into a pipe, and that is provided with a through aperture via which a flow can pass. The partition-receiving face of each of the elements, in which face the aperture opens out, is a concave face, the partition-receiving faces of the two shutter elements facing each other. The partition is a blade hinged via two opposite ones of its sides and situated between the two partition-receiving faces, the blade having a rest position between the two partition-receiving faces in the event that the pressure inside the vehicle is equal to the pressure outside said vehicle, and being pressed against one or other of the partition-receiving faces in the event of sudden change between the pressure inside the vehicle and the pressure outside said vehicle.
Document CH 492 910 (1968) to BATELLE MEMORIAL INSTITUTE describes a shutter element that may be a part that fits snugly inside a pipe, and that is provided with a through aperture via which air can flow. The partition-receiving face of the element, in which face the aperture opens out, is a concave face, the partition being a blade hinged via two opposite ones of its sides.
The shutter devices described in the last-mentioned documents suffer from the drawbacks of being complex and fragile.
Moreover, the shutter devices described in said last-mentioned documents suffer from the major drawback of only enabling a distribution duct to be shut off locally and to a limited extent, and therefore of only being usable at the inlet or at the outlet of the distribution duct.